A heightened interest has developed amongst consumers and others in determining whether specified environments contain allergens such as dust mites, storage mites, cockroaches, animal dander, rodent urine, molds and endotoxin. Consumers have a particular interest in minimizing such substances in living and sleeping areas in order to control health conditions such as asthma and allergic reactions, while professionals are more concerned with the sterile nature of work environments.
Many individuals develop allergic reactions to one or more of the allergens listed above when found within their home. Household allergens can cause a variety of allergic symptoms such as sneezing, nasal congestion and a runny nose (perennial rhinitis), wheezing, breathlessness and mild, moderate or severe asthma. In some cases, exposure to indoor allergens can also cause allergic skin disease also known as eczema (or atopic dermatitis). Overall, approximately 20-30% of the population is allergic to one or more indoor allergens. Approximately 80% of children with asthma or nasal symptoms are allergic to indoor allergens. Asthma due to indoor allergens is an important clinical problem. Asthma accounts for approximately 1 out of every 7 visits of children to hospital emergency rooms. Some children may grow out of asthma by adolescence but in others the condition persists into adulthood.
With outdoor pollen allergens, the symptoms go away after the pollen season, but in the case of household allergens, patients are continuously exposed year round. This results in persistent inflammation of the nose or lungs. This kind of inflammation is caused by other chemicals (called leukotrienes) and includes other cells (called eosinophils). Once inflamed, the lungs become supersensitive (or hyperreactive) and can react to other substances. This is the reason why asthma attacks can be triggered by virus infection, tobacco smoke, chemicals, stress or exercise. Becoming allergic to household allergens is one of the first steps in developing asthma. Once asthma develops the symptoms can be triggered by infection, other substances in the environment, and physical activity.
One type of triggering allergen is the dust mite. House dust mites are 8 legged microscopic creatures that are closely related to spiders and ticks. Dust mites are about ⅓ of a millimeter long. They are barely visible to the naked eye but can be seen with a low power microscope. House dust mites are designed to live with humans. They feed mainly on human skin scales but can also feed on animal skin scales and debris found in dust. Humans shed approximately 5 grams of skin scales per week, which is enough to feed many thousands of mites. Mites thrive at temperatures of 70-72° F. and a relatively humidity of 75%. These warm, humid conditions are exactly the same as those favored by most humans. Large populations of mites are found in beds, pillows, bedding (blankets, comforters etc.) and bedroom carpets. Furry and other soft toys are also good homes for house dust mites. Fitted carpets and soft furnishings (sofas and chairs) are other common sites of mite infestation. Mites burrow down into carpet pile and into padded furniture. Carpets fitted onto concrete slabs in basements often become damp and harbor large numbers of mites.
To assess the level of mite infestation, acarologists measure mites present in a house dust sample. Such a measurement can either be made by counting mites or other allergens per gram of dust or by measuring specific mite, cat, dog, cockroach or fungal allergens in dust samples through an enzyme-linked immunosorbent assay (ELISA). In the case of mites, a low level is less than 20 mites per gram of dust. Allergies develop when people are exposed to approximate 100 mites per gram (or more). Heavy mite infestation is greater than 500 mites per gram dust. Allergic individuals are likely to have symptoms if they are continually exposed to dust containing more than 500 mites/g. Some highly sensitive patients may have symptoms when exposed to dust with lower mite counts. An ELISA test can be configured to visually indicate when specific levels of allergens are present in a sample.
The traditional method for assessing exposure to dust mites and other household allergens has been through collection and analysis of a dust sample taken from a test site. The typical way to collect such a sample has been to attach a suction device to a nozzle containing a filter trap so as to draw air from the test site into the nozzle and, hence, through the filter. The resulting collected dust sample can then be tested to determine the dust mite per gram. The problem with this method is its inflexibility. It typically requires use of a suction device dedicated for use with the nozzle or, at best, permits very limited use of alternative sources of suction such as vacuum cleaners simply because of the narrow range of hose connection sizes accommodated by the nozzle. This restricts the direct access of consumers to use of such test devices and thereby may often result in no such tests being performed where they should be or in the necessity to hire an outside service provider at a relatively substantial cost to come to the home to collect the necessary dust sample. There are adapter tubes and extension kits usable for vacuum cleaner hoses which accept hoses of several dimensions. However, these adapters and extension kits are clumsy to use due to their length and size and, in addition, can accommodate only a relatively small number of different hose diameters. Furthermore, these alternative devices do not lend themselves to compact packaging and mailing requirements. In addition, long tubes are not suitable either for insertion and extraction in situ of the small filter traps used to collect dust or for sealing to conduct in situ tests with a small volume of liquid. What is needed is an inexpensive, compact structure which is adaptable for use with a large variety of consumer and/or commercial vacuum cleaners having different hose diameters.